The human corneal endothelium forms an essential layer of the cornea, maintaining corneal transparency through the regulation of corneal hydration. The endothelial cell layer does not actively regenerate in vivo. Hence, there remains a need for corneal allograft transplantation in cases of accelerated endothelial cell loss due to genetic disease, generic eye infection, or more acute cell loss caused by accidental and surgical trauma or previous corneal surgery. Although current corneal transplantation is successful in the short term, there is a risk of graft rejection, and long-term graft failure is a problem. Moreover, global shortage of cornea donors greatly restricts the number of corneal transplantation performed.
It is now possible to isolate and culture human corneal endothelial cells (HCECs) in vitro, thus providing new opportunity for in-depth cell biological studies and development of potential tissue-engineered human corneal endothelium graft alternative. In order to generate the required numbers of HCECs for further biological studies and future development of tissue-engineered human corneal endothelium, isolated primary HCECs must be propagated for at least three rounds of passages to achieve a sizeable amount of cells for experimental research. However, on repeated passages, the human corneal endothelial cells may develop into fibroblastic-like cells.
It is therefore desirable to develop effective techniques (for example either a novel approach or a single culture medium) to support the propagation of isolated HCECs, as well as to maintain their characteristic morphology.